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arXiv · 2307.03713

Different fractional charges from auto- and cross-correlation noise in quantum Hall states without upstream modes

Navketan Batra·D. E. Feldman
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Abstract

Fractional charges of anyons can be extracted from shot noise in two ways. One can use either the auto-correlation noise of the current in one drain or the cross-correlation noise between two drains on the two sides of the device. The former approach typically overestimates the charge. This may happen due to upstream edge modes. We propose a mechanism for the excess auto-correlation noise without upstream modes. It applies to systems with multiple co-propagating edge modes and assumes that the noise is measured at a low but non-zero frequency.

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Navketan Batra, D. E. Feldman. 2023-07-07. Different fractional charges from auto- and cross-correlation noise in quantum Hall states without upstream modes. https://doi.org/10.1103/physrevlett.132.226601

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